Keyhole lock



Dec. 1l, 1951 J, ELSBERG 2,577,956

KEY HOLE LOCK Filed March 6, 1950 ff fg if .fa l fz |I|I-"'A ff fa lul U um Y l ...null o I y? INVENTOR.

Patented Dec. 11, 1951 U Nil Tlll)` STATES F 'F4 IC EI KEYHOLE LOCK `Tohu Elslierg, York, Ni Yi Application March 6, 1950, Serial No; 147.94D,=

1.'. This invention relates to a key hole lock. It is an object ofi thelpresentzinvention to provide av key hole lock adaptedto be inserted` in.

a key hole. and prevent'. the admission. to the keyhole oa key from the outside and.v to prevent tampering with the door lock and thereby to provide means which cannot be removed from the key hole in order to permit the key of one attempting to enter the room from being used.

Other objects of the present invention are to provide a key hole lock which is of simple construction, inexpensive to manufacture, has a minimum number of parts, easy to insert and remove from the key hole and eicient in operation.

For other objects and for a better understanding of the invention, reference may be had to the following detailed description taken in connection with the accompanying drawing, in which Fig. 1 is a perspective view of the key hole lock embodying the features of the present invention.

Fig. 2 is a perspective view oi the slide in its released position adapted to prevent the easy removal of the key hole lock from the inside of the room having the door.

Fig. 3 is a longitudinal sectional view taken on line 3-3 of Fig. l.

Fig. 4 is an elevational view showing the key hole lock being inserted within a key hole and the latching member elevated, the slide being in its original position.

Fig. 5 is a view similar to Fig. 4, but with the slide having been adjusted upon the operating member and latched with the operating teeth thereof.

Referring now to the figures, I0 represents the main body formed of a strip of material bent into U-shape and an internal member II which has an inclined edge I2 and is secured by pins I3 and I4 to the open under side of the body I6. The member II has a depending projection I5 adapted to engage with the lock face in the door to prevent the further inward projection of the device. The body carries a slide or operating member I6 and a latch hook II that is lifted by the slide as the operating member is pulled by its handle I8 inwardly. The latch hook I1 is pivoted to the main body I0 by a pin I9. A leaf spring 2| reacts between the closed folded upper portion of the body I0 to urge the latch hook I1 downwardlyv onto the slide ,46. The slide I6 has a curved upper edge 22 that serves aS a cam to effect the lifting action of the latch 2. claims. (c1. 'm1-424) hook I'T. The member Iil. having the inclined edge I2' extends' inwardly beyond' the f'olded' strip ofthe body in orderjto provide adequate support for the* operatingy member'V I6;

The operating memberA I6" has an elongated slot 23" through which extends apin` 2'4 carried by the body and whereby the operating member will be limited in its inward and outward movement with respect to the main body.

The upper edge of the operating member has .rack teeth 25 adapted to receive a slide lock 26.

The slide lock 26 reacts against the edge of the body I0 so as to keep the operating member in its pulled out position and the hook latch I1 elevated.

Once the key hole lock is inserted and the parts are adjusted to elevate the hook latch I'I, any insertion of a key on the outer side of the door is prohibited and there is provided a stop which cannot be readily releasedirom the door.

The slide lock 26 comprises a slotted member 28 having slot 29 and portions 3I adapted to enter spaces between the teeth 25. When the lock slide 26 is not in use, it can be secured in a wide notch 32 on the operating member I6. The slotted member 28 is held in place when a pivot arm 33 with its projection 34 is lowered so that the projection 34 enters a hole 35 in the side of the slotted member 28 so as to engage with the under edge of the operating member I6 and prevent the upward displacement of the slide lock. A pin 36 prevents the removal of the lock slide 26 from the operating member I6.

While various changes may be made in the detail construction, it shall be understood that such changes shall be within the spirit and scope of the present invention as defined by the appended claims.

Having thus set forth and disclosed the nature of my invention, what is claimed is:

l. A key hole lock comprising a body member, a slide forming an operating member operable in the body member and having a cam surface, a hook latch pivotable in the body member and co-acting with the cam surface of the operating member to be operated, said operating member being longitudinally adjustable through the body member, and a slide lock device on the operating member adapted to hold the operating member against inward displacement relative to the body member when the latch has been projected, and said operating member having ratchet teeth, said slide lock having portions entering spaces between the ratchet teeth whereby to positively lock the slide lock against longitudinal displacement upon the operating member. said slide lock having a pivot latch thereon engageable with the operating member to hold the slide lock device against lateral displacement once said portions thereof are disposed in the spaces between the ratchet teeth.

2. A key hole lock comprising an elongated body member having an opening extending longitudinally therethrough, a slide member extending .adjustably through the opening in the body member and having a concave cam surface along a portion of the upper edge thereof. an elongated hook latch pivoted at one end in the body member and extending with its other end out through said opening thereof above the cam surface of the slide member. a spring in said body member biasing said hook latch down- 4 ment of the latter with respect to said body member, a latch hinged to said slide lock device in a position to swing into and from a latching position about a substantially horizontal pivot axis parallel to the longitudinal dimension o! said slide member, said slide lock device having a side aperture below the level of the lower edge of the slide member, and a locking projection on said latch in effective position to enter said side aperture in latching position of said latch and extend beneath said lower edge of said slide member and prevent raising thereof and disengagement of the downwardly extending edge portions on said slide lock device from the teeth on said slide member.

JOHN ELSBERG.

' vmarvamarzclas CITED The following references are of record in the file of this patent:

FOREIGN PATENTS Number Country Date 23,674 Great Britain Oct. 24,'1906 381,403

Germany Sept. 20, 1923 

